<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html lang="en" dir="ltr" class="client-nojs">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>static specifier - cppreference.com</title>
<meta charset="UTF-8">
<meta name="generator" content="MediaWiki 1.21.2">


<link rel="shortcut icon" href="../../../favicon.ico">



<link rel="stylesheet" href="../../../common/ext.css">
<meta name="ResourceLoaderDynamicStyles" content="">
<link rel="stylesheet" href="../../../common/site_modules.css">
<style>a:lang(ar),a:lang(ckb),a:lang(fa),a:lang(kk-arab),a:lang(mzn),a:lang(ps),a:lang(ur){text-decoration:none}#toc{display:none}.editsection{display:none}
/* cache key: mwiki1-mwiki_en_:resourceloader:filter:minify-css:7:472787eddcf4605d11de8c7ef047234f */</style>

<script src="../../../common/startup_scripts.js"></script>
<script>if(window.mw){
mw.config.set({"wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"cpp/language/static","wgTitle":"cpp/language/static","wgCurRevisionId":68749,"wgArticleId":5288,"wgIsArticle":true,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":[],"wgBreakFrames":false,"wgPageContentLanguage":"en","wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy","wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgMonthNamesShort":["","Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"],"wgRelevantPageName":"cpp/language/static","wgRestrictionEdit":[],"wgRestrictionMove":[]});
}</script><script>if(window.mw){
mw.loader.implement("user.options",function(){mw.user.options.set({"ccmeonemails":0,"cols":80,"date":"default","diffonly":0,"disablemail":0,"disablesuggest":0,"editfont":"default","editondblclick":0,"editsection":0,"editsectiononrightclick":0,"enotifminoredits":0,"enotifrevealaddr":0,"enotifusertalkpages":1,"enotifwatchlistpages":0,"extendwatchlist":0,"externaldiff":0,"externaleditor":0,"fancysig":0,"forceeditsummary":0,"gender":"unknown","hideminor":0,"hidepatrolled":0,"imagesize":2,"justify":0,"math":1,"minordefault":0,"newpageshidepatrolled":0,"nocache":0,"noconvertlink":0,"norollbackdiff":0,"numberheadings":0,"previewonfirst":0,"previewontop":1,"quickbar":5,"rcdays":7,"rclimit":50,"rememberpassword":0,"rows":25,"searchlimit":20,"showhiddencats":0,"showjumplinks":1,"shownumberswatching":1,"showtoc":0,"showtoolbar":1,"skin":"cppreference2","stubthreshold":0,"thumbsize":2,"underline":2,"uselivepreview":0,"usenewrc":0,"watchcreations":0,"watchdefault":0,"watchdeletion":0,
"watchlistdays":3,"watchlisthideanons":0,"watchlisthidebots":0,"watchlisthideliu":0,"watchlisthideminor":0,"watchlisthideown":0,"watchlisthidepatrolled":0,"watchmoves":0,"wllimit":250,"variant":"en","language":"en","searchNs0":true,"searchNs1":false,"searchNs2":false,"searchNs3":false,"searchNs4":false,"searchNs5":false,"searchNs6":false,"searchNs7":false,"searchNs8":false,"searchNs9":false,"searchNs10":false,"searchNs11":false,"searchNs12":false,"searchNs13":false,"searchNs14":false,"searchNs15":false,"gadget-ColiruCompiler":1});;},{},{});mw.loader.implement("user.tokens",function(){mw.user.tokens.set({"editToken":"+\\","patrolToken":false,"watchToken":false});;},{},{});
/* cache key: mwiki1-mwiki_en_:resourceloader:filter:minify-js:7:ca03345b1e2c4d90a25d968753a73b92 */
}</script>
<script>if(window.mw){
mw.loader.load(["mediawiki.page.startup","mediawiki.legacy.wikibits","mediawiki.legacy.ajax"]);
}</script>
<style type="text/css">/*<![CDATA[*/
.source-cpp {line-height: normal;}
.source-cpp li, .source-cpp pre {
	line-height: normal; border: 0px none white;
}
/**
 * GeSHi Dynamically Generated Stylesheet
 * --------------------------------------
 * Dynamically generated stylesheet for cpp
 * CSS class: source-cpp, CSS id: 
 * GeSHi (C) 2004 - 2007 Nigel McNie, 2007 - 2008 Benny Baumann
 * (http://qbnz.com/highlighter/ and http://geshi.org/)
 * --------------------------------------
 */
.cpp.source-cpp .de1, .cpp.source-cpp .de2 {font: normal normal 1em/1.2em monospace; margin:0; padding:0; background:none; vertical-align:top;}
.cpp.source-cpp  {font-family:monospace;}
.cpp.source-cpp .imp {font-weight: bold; color: red;}
.cpp.source-cpp li, .cpp.source-cpp .li1 {font-weight: normal; vertical-align:top;}
.cpp.source-cpp .ln {width:1px;text-align:right;margin:0;padding:0 2px;vertical-align:top;}
.cpp.source-cpp .li2 {font-weight: bold; vertical-align:top;}
.cpp.source-cpp .kw1 {color: #0000dd;}
.cpp.source-cpp .kw2 {color: #0000ff;}
.cpp.source-cpp .kw3 {color: #0000dd;}
.cpp.source-cpp .kw4 {color: #0000ff;}
.cpp.source-cpp .co1 {color: #909090;}
.cpp.source-cpp .co2 {color: #339900;}
.cpp.source-cpp .coMULTI {color: #ff0000; font-style: italic;}
.cpp.source-cpp .es0 {color: #008000; font-weight: bold;}
.cpp.source-cpp .es1 {color: #008000; font-weight: bold;}
.cpp.source-cpp .es2 {color: #008000; font-weight: bold;}
.cpp.source-cpp .es3 {color: #008000; font-weight: bold;}
.cpp.source-cpp .es4 {color: #008000; font-weight: bold;}
.cpp.source-cpp .es5 {color: #008000; font-weight: bold;}
.cpp.source-cpp .br0 {color: #008000;}
.cpp.source-cpp .sy0 {color: #008000;}
.cpp.source-cpp .sy1 {color: #000080;}
.cpp.source-cpp .sy2 {color: #000040;}
.cpp.source-cpp .sy3 {color: #000040;}
.cpp.source-cpp .sy4 {color: #008080;}
.cpp.source-cpp .st0 {color: #008000;}
.cpp.source-cpp .nu0 {color: #000080;}
.cpp.source-cpp .nu6 {color: #000080;}
.cpp.source-cpp .nu8 {color: #000080;}
.cpp.source-cpp .nu12 {color: #000080;}
.cpp.source-cpp .nu16 {color:#000080;}
.cpp.source-cpp .nu17 {color:#000080;}
.cpp.source-cpp .nu18 {color:#000080;}
.cpp.source-cpp .nu19 {color:#000080;}
.cpp.source-cpp .ln-xtra, .cpp.source-cpp li.ln-xtra, .cpp.source-cpp div.ln-xtra {background-color: #ffc;}
.cpp.source-cpp span.xtra { display:block; }

/*]]>*/
</style>
<!--[if lt IE 7]><style type="text/css">body{behavior:url("/mwiki/skins/cppreference2/csshover.min.htc")}</style><![endif]-->
</head>
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_language_static skin-cppreference2 action-view cpp-navbar">
        <!-- header -->
        
        <!-- /header -->
        <!-- content -->
        <div id="cpp-content-base">
            <div id="content">
                <a id="top"></a>
                <div id="mw-js-message" style="display:none;"></div>
                                <!-- firstHeading -->
                <h1 id="firstHeading" class="firstHeading">static specifier</h1>
                <!-- /firstHeading -->
                <!-- bodyContent -->
                <div id="bodyContent">
                                        <!-- tagline -->
                    <div id="siteSub">From cppreference.com</div>
                    <!-- /tagline -->
                                        <!-- subtitle -->
                    <div id="contentSub"><span class="subpages">&lt; <a href="../../cpp.html" title="cpp">cpp</a>‎ | <a href="../language.1.html" title="cpp/language">language</a></span></div>
                    <!-- /subtitle -->
                                                            <!-- bodycontent -->
                    <div id="mw-content-text" lang="en" dir="ltr" class="mw-content-ltr">
<div class="t-navbar" style="">
<div class="t-navbar-sep"> </div>
<div class="t-navbar-head">
<a href="../../cpp.html" title="cpp"> C++</a><div class="t-navbar-menu"><div>
<div><table class="t-nv-begin" cellpadding="0" style="line-height:1.1em;">
<tr class="t-nv"><td colspan="5"> <a href="../language.1.html" title="cpp/language"> Language</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../header.html" title="cpp/header"> Standard library headers</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../concept.html" title="cpp/concept"> Concepts</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../utility.html" title="cpp/utility"> Utilities library</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../string.html" title="cpp/string"> Strings library</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../container.html" title="cpp/container"> Containers library</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../algorithm.html" title="cpp/algorithm"> Algorithms library</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../iterator.html" title="cpp/iterator"> Iterators library</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../numeric.html" title="cpp/numeric"> Numerics library</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../io.html" title="cpp/io"> Input/output library</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../locale.html" title="cpp/locale"> Localizations library</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../regex.html" title="cpp/regex"> Regular expressions library</a> <span class="t-mark-rev t-since-cxx11">(C++11)</span> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../atomic.html" title="cpp/atomic"> Atomic operations library</a> <span class="t-mark-rev t-since-cxx11">(C++11)</span> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="../thread.html" title="cpp/thread"> Thread support library</a> <span class="t-mark-rev t-since-cxx11">(C++11)</span> </td></tr>
</table></div>
<div></div>
</div></div>
</div>
<div class="t-navbar-sep"> </div>
<div class="t-navbar-head"><a href="../language.1.html" title="cpp/language"> C++ language</a></div>
<div class="t-navbar-sep"> </div>
<div class="t-navbar-head">
<a href="classes.html" title="cpp/language/classes"> Classes</a><div class="t-navbar-menu"><div>
<div style="display:inline-block">
<div><table class="t-nv-begin" cellpadding="0" style="">
<tr class="t-nv-h2"><td colspan="5"> General </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="classes.html" title="cpp/language/classes"> overview</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="class.html" title="cpp/language/class"> class/struct types</a> </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="union.html" title="cpp/language/union"> union types</a> </td></tr>
<tr class="t-nv-h2"><td colspan="5"> Members </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="data_members.html" title="cpp/language/data members">data members</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <strong class="selflink">static members</strong>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="this.html" title="cpp/language/this">the <code>this</code> pointer</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="nested_types.html" title="cpp/language/nested types">nested classes</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="member_template.html" title="cpp/language/member template">member templates</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="bit_field.html" title="cpp/language/bit field">bit fields</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="using_declaration.html" title="cpp/language/using declaration">using-declarations</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="member_functions.html" title="cpp/language/member functions">member functions</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="access.html" title="cpp/language/access">member access specifiers</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="initializer_list.html" title="cpp/language/initializer list">constructor initializer list</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="data_members.html%23Member_initialization" title="cpp/language/data members">in-class <i>brace-or-equal</i> initializer</a><span class="t-mark-rev t-since-cxx11">(C++11)</span>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="friend.html" title="cpp/language/friend"><code>friend</code> specifier</a>
</td></tr>
<tr class="t-nv-h2"><td colspan="5"> Special member functions </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="default_constructor.html" title="cpp/language/default constructor">default constructor</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="copy_constructor.html" title="cpp/language/copy constructor">copy constructor</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="move_constructor.html" title="cpp/language/move constructor">move constructor</a><span class="t-mark-rev t-since-cxx11">(C++11)</span>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="as_operator.html" title="cpp/language/as operator">copy assignment operator</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="move_operator.html" title="cpp/language/move operator">move assignment operator</a><span class="t-mark-rev t-since-cxx11">(C++11)</span>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="destructor.html" title="cpp/language/destructor">destructor</a>
</td></tr>
<tr class="t-nv-h2"><td colspan="5"> Inheritance </td></tr>
<tr class="t-nv"><td colspan="5"> <a href="derived_class.html" title="cpp/language/derived class">base and derived classes</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="virtual.html" title="cpp/language/virtual">virtual member functions</a>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="override.html" title="cpp/language/override">override</a><span class="t-mark-rev t-since-cxx11">(C++11)</span>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="final.html" title="cpp/language/final">final</a><span class="t-mark-rev t-since-cxx11">(C++11)</span>
</td></tr>
<tr class="t-nv"><td colspan="5"> <a href="abstract_class.html" title="cpp/language/abstract class">pure virtual functions and abstract classes</a>
</td></tr>
</table></div>
</div>
<div></div>
</div></div>
</div>
<div class="t-navbar-sep"> </div>
</div>
<p>Inside a class, declares members not bound to specific instances.
</p>
<table id="toc" class="toc"><tr><td>
<div id="toctitle"><h2>Contents</h2></div>
<ul>
<li class="toclevel-1 tocsection-1"><a href="static.html%23Syntax"><span class="tocnumber">1</span> <span class="toctext">Syntax</span></a></li>
<li class="toclevel-1 tocsection-2">
<a href="static.html%23Explanation"><span class="tocnumber">2</span> <span class="toctext">Explanation</span></a>
<ul>
<li class="toclevel-2 tocsection-3"><a href="static.html%23Static_member_functions"><span class="tocnumber">2.1</span> <span class="toctext">Static member functions</span></a></li>
<li class="toclevel-2 tocsection-4"><a href="static.html%23Static_data_members"><span class="tocnumber">2.2</span> <span class="toctext">Static data members</span></a></li>
<li class="toclevel-2 tocsection-5"><a href="static.html%23Constant_static_members"><span class="tocnumber">2.3</span> <span class="toctext">Constant static members</span></a></li>
</ul>
</li>
<li class="toclevel-1 tocsection-6"><a href="static.html%23References"><span class="tocnumber">3</span> <span class="toctext">References</span></a></li>
<li class="toclevel-1 tocsection-7"><a href="static.html%23See_also"><span class="tocnumber">4</span> <span class="toctext">See also</span></a></li>
</ul>
</td></tr></table>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Syntax">edit</a>]</span> <span class="mw-headline" id="Syntax">Syntax</span>
</h3>
<table class="t-sdsc-begin">

<tr>
<td colspan="10" class="t-sdsc-sep">
</td>
</tr>
<tr class="t-sdsc">
<td class="t-sdsc-nopad"> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">static</span></span></span> <span class="t-spar">data_member</span>
</td>
<td class="t-sdsc-nopad">
</td>
<td class="t-sdsc-nopad">
</td>
</tr>



<tr>
<td colspan="10" class="t-sdsc-sep">
</td>
</tr>
<tr class="t-sdsc">
<td class="t-sdsc-nopad"> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">static</span></span></span> <span class="t-spar">member_function</span>
</td>
<td class="t-sdsc-nopad">
</td>
<td class="t-sdsc-nopad">
</td>
</tr>



<tr>
<td colspan="10" class="t-sdsc-sep">
</td>
</tr>
</table>
<div class="t-li1">
<span class="t-li">1)</span> Declares a static data member: </div>
<div class="t-li1">
<span class="t-li">2)</span> Declares a static member function.</div>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Explanation">edit</a>]</span> <span class="mw-headline" id="Explanation">Explanation</span>
</h3>
<p>Static members of a class are not associated with the objects of the class: they are independent objects with <a href="storage_duration.html" title="cpp/language/storage duration">static storage duration</a> or regular functions defined in namespace scope, only once in the program.
</p>
<p>The <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">static</span></span></span> keyword is only used with the declaration of a static member, inside the class definition, but not with the definition:
</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="cpp source-cpp"><pre class="de1"><span class="kw1">class</span> X <span class="br0">{</span>
    <span class="kw4">static</span> <span class="kw4">int</span> n<span class="sy4">;</span> <span class="co1">// declaration (uses 'static')</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">int</span> X<span class="sy4">::</span><span class="me2">n</span> <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span> <span class="co1">// definition (does not use 'static')</span></pre></div></div>
<p>The declaration inside the class body is not a definition and may declare the member to be of <a href="incomplete_type.html" title="cpp/language/incomplete type" class="mw-redirect">incomplete type</a> (other than <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span></span></span>), including the type in which the member is declared.
</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="cpp source-cpp"><pre class="de1"><span class="kw1">struct</span> Foo<span class="sy4">;</span>
<span class="kw1">struct</span> S <span class="br0">{</span>
   <span class="kw4">static</span> <span class="kw4">int</span> a<span class="br0">[</span><span class="br0">]</span><span class="sy4">;</span> <span class="co1">// incomplete type</span>
   <span class="kw4">static</span> Foo x<span class="sy4">;</span> <span class="co1">// incomplete type</span>
   <span class="kw4">static</span> S s<span class="sy4">;</span> <span class="co1">// incomplete type (inside its own definition)</span>
<span class="br0">}</span><span class="sy4">;</span>
 
<span class="kw4">int</span> S<span class="sy4">::</span><span class="me2">a</span><span class="br0">[</span><span class="nu0">10</span><span class="br0">]</span><span class="sy4">;</span> <span class="co1">// definition, complete type</span>
<span class="kw1">struct</span> Foo <span class="br0">{</span><span class="br0">}</span><span class="sy4">;</span>
Foo S<span class="sy4">::</span><span class="me2">x</span><span class="sy4">;</span> <span class="co1">// definition, complete type</span>
S S<span class="sy4">::</span><span class="me2">s</span><span class="sy4">;</span> <span class="co1">// definition, complete type</span></pre></div></div>
<p>To refer to a static member <code>n</code> of class <code>T</code>, two forms may be used: qualified name <code>T::m</code> or member access expression <code>e.m</code> or <code>e-&gt;m</code>, where <code>e</code> is an expression that evaluates to <code>T</code> or <code>T*</code> respectively. When in the same class scope, the qualification is unnecessary:
</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="cpp source-cpp"><pre class="de1"><span class="kw1">struct</span> X <span class="br0">{</span>
    <span class="kw4">static</span> <span class="kw4">void</span> f<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// function declaration</span>
    <span class="kw4">static</span> <span class="kw4">int</span> n<span class="sy4">;</span> <span class="co1">// member declaration</span>
<span class="br0">}</span><span class="sy4">;</span>
 
X g<span class="br0">(</span><span class="br0">)</span> <span class="br0">{</span> <span class="kw1">return</span> X<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</span> <span class="co1">// some function returning X</span>
 
<span class="kw4">void</span> f<span class="br0">(</span><span class="br0">)</span> <span class="br0">{</span>
    X<span class="sy4">::</span><span class="me2">f</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>  <span class="co1">// qualified name access to static function</span>
    g<span class="br0">(</span><span class="br0">)</span>.<span class="me1">f</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// expression member access to static function</span>
<span class="br0">}</span>
 
<span class="kw4">int</span> X<span class="sy4">::</span><span class="me2">n</span> <span class="sy1">=</span> <span class="nu0">7</span><span class="sy4">;</span> <span class="co1">// definition</span>
 
<span class="kw4">void</span> X<span class="sy4">::</span><span class="me2">f</span><span class="br0">(</span><span class="br0">)</span> <span class="br0">{</span> <span class="co1">// definiton</span>
    n <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span> <span class="co1">// X::n is accessible as just n in this scope.</span>
<span class="br0">}</span></pre></div></div>
<p>Static members obey the class member access rules (private, protected, public).
</p>
<h4>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Static member functions">edit</a>]</span> <span class="mw-headline" id="Static_member_functions">Static member functions</span>
</h4>
<p>Static member functions are not associated with any object. When called, they have no <span class="t-c"><span class="mw-geshi cpp source-cpp">this</span></span> pointer. They cannot be <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">virtual</span></span></span>, <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span></span></span>, or <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">volatile</span></span></span>. They cannot access non-static data members of the class. Address of a static member function may be stored in a regular pointer to function, but not in a pointer to member function.
</p>
<h4>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Static data members">edit</a>]</span> <span class="mw-headline" id="Static_data_members">Static data members</span>
</h4>
<p>The static member objects are not part of the object. If the static member is declared thread_local<span class="t-mark-rev t-since-cxx11">(since C++11)</span>, there is one such object per thread. Otherwise, there is only one instance of the static member object in the entire program, with static <a href="storage_duration.html" title="cpp/language/storage duration">storage duration</a>. The static members exist even if no objects of the class have been defined.
</p>
<p>Static data members cannot be <span class="t-c"><span class="mw-geshi cpp source-cpp">mutable</span></span>.
</p>
<p>Static data members of classes in namespace scope have <a href="storage_duration.html" title="cpp/language/storage duration">external linkage</a>.
</p>
<p>Local classes (classes defined inside functions) and unnamed classes, including member classes of unnamed classes, cannot have static data members.
</p>
<h4>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Constant static members">edit</a>]</span> <span class="mw-headline" id="Constant_static_members">Constant static members</span>
</h4>
<p>If a static data member of integral or enumeration type is declared <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span></span></span> (and not <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">volatile</span></span></span>), it can be initialized with a <a href="data_members.html%23Member_initialization" title="cpp/language/data members">brace-or-equal initializer</a> that is a <a href="constexpr.html" title="cpp/language/constexpr">constant expression</a>, right inside the class definition. In this case, no definition is needed:
</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="cpp source-cpp"><pre class="de1"><span class="kw1">struct</span> X <span class="br0">{</span>
    <span class="kw4">const</span> <span class="kw4">static</span> <span class="kw4">int</span> n <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
    <span class="kw4">const</span> <span class="kw4">static</span> <span class="kw4">int</span> m<span class="br0">{</span><span class="nu0">2</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// since C++11</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="co1">// const int X::n = 2; // ERROR: redefinition</span></pre></div></div>
 <table class="t-rev-begin">
<tr class="t-rev t-since-cxx11">
<td>
<p>If a static data member of <a href="../concept/LiteralType.html" title="cpp/concept/LiteralType"><code>LiteralType</code></a> is declared <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span></span></span>, it can be initialized with a brace-or-equal initializer that is a constant expression inside the class definition. A definition at namespace scope is still required, but it should not have an initializer:
</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="cpp source-cpp"><pre class="de1"><span class="kw1">struct</span> X <span class="br0">{</span>
    <span class="kw4">constexpr</span> <span class="kw4">static</span> <span class="kw4">int</span> n <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">int</span> X<span class="sy4">::</span><span class="me2">n</span><span class="sy4">;</span></pre></div></div>
</td>
<td><span class="t-mark-rev t-since-cxx11">(since C++11)</span></td>
</tr>
</table>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: References">edit</a>]</span> <span class="mw-headline" id="References">References</span>
</h3>
<div class="t-ref-std-c++11">
<ul><li> C++11 standard (ISO/IEC 14882:2011): 
</li></ul>
<dl><dd>
<ul><li> 9.4 Static members [class.static]
</li></ul>
</dd></dl>
</div>
<div class="t-ref-std-c++98">
<ul><li> C++98 standard (ISO/IEC 14882:1998): 
</li></ul>
<dl><dd>
<ul><li> 9.4 Static members [class.static]
</li></ul>
</dd></dl>
</div>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: See also">edit</a>]</span> <span class="mw-headline" id="See_also">See also</span>
</h3>
<ul><li> <a href="storage_duration.html" title="cpp/language/storage duration"><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">static</span></span></span> storage specifier</a>
</li></ul>

<!-- 
NewPP limit report
Preprocessor visited node count: 1183/1000000
Preprocessor generated node count: 3336/1000000
Post‐expand include size: 36929/2097152 bytes
Template argument size: 5469/2097152 bytes
Highest expansion depth: 13/40
Expensive parser function count: 0/100
-->

<!-- Saved in parser cache with key mwiki1-mwiki_en_:pcache:idhash:5288-0!*!0!!en!*!* and timestamp 20140521193741 -->
</div>                    <!-- /bodycontent -->
                                        <!-- printfooter -->
                    <div class="printfooter">
                    Retrieved from "<a href="http%3A//en.cppreference.com/mwiki/index.php">http://en.cppreference.com/mwiki/index.php?title=cpp/language/static&amp;oldid=68749</a>"                    </div>
                    <!-- /printfooter -->
                                                            <!-- catlinks -->
                    <div id="catlinks" class="catlinks catlinks-allhidden"></div>                    <!-- /catlinks -->
                                                            <div class="visualClear"></div>
                    <!-- debughtml -->
                                        <!-- /debughtml -->
                </div>
                <!-- /bodyContent -->
            </div>
        </div>
        <!-- /content -->
        <!-- footer -->
        
        <!-- /footer -->
        <script>if(window.mw){
mw.loader.state({"site":"loading","user":"missing","user.groups":"ready"});
}</script>
<script src="../../../common/skin_scripts.js"></script>
<script>if(window.mw){
mw.loader.load(["mediawiki.action.view.postEdit","mediawiki.user","mediawiki.page.ready","mediawiki.searchSuggest","mediawiki.hidpi","ext.gadget.ColiruCompiler"], null, true);
}</script>
<script src="../../../common/site_scripts.js"></script>

<script type="text/javascript">
var _gaq = _gaq || [];
_gaq.push(['_setAccount', 'UA-2828341-1']);
_gaq.push(['_setDomainName', 'cppreference.com']);
_gaq.push(['_trackPageview']);
</script><!-- Served in 2.377 secs. -->
	</body>
<!-- Cached 20140521193742 -->
</html>
